Digitized images of autoradiographs showing cerebral metabolic activity in serial parallel microtomed sliced sections of experimental animal brains are to be enhanced, aligned, stacked, and viewed at any arbitrary cutting surface, and procedures and algorithms are to be readily transportable to an NIMH image processing system. Alignment work has begun using the Evans and Sutherland System. Initially, it is intended to use the 60 cubed volume-element 3-dimensional block model software already operational on the System. The host NIMH Image Processing System has been installed.